1. Field of the Invention
This invention relates to silicate foam insulating and structural compositions. In one aspect the invention relates to an improved strength silicate foam composition. In another aspect this invention relates to a method for increasing the strength of silicate foam compositions without substantially altering the density of such foam compositions.
2. Brief Description of the Prior Art
Aqueous silicate compositions have been used extensively for specialized applications such as cements, insulation, coatings, and matrix for refractory or ablation aggregate. Silicate foam is inherently fire resistant and has excellent insulation properties. The heat transfer coefficient of silicate foam compares favorable with that of polystyrene and polyurethane foam, and silicate foam has a decomposition temperature more than five times greater than these well-known insulating foams.
A prefiling search was made on the concept of the present invention wherein the strength of a silicate foam composition is increased by the incorporation of a vinyl chloride telomer into said foam composition. No patents were located depicting the concept.
Even with extensive work in the art, prior art silicate foam compositions have not been practical because of poor water resistance, low strength, and difficulties in fabrication of a foam structure. Prior art compositions could not be practically fabricated into shapes due to composition instability and excess shrinkage. Furthermore, these compositions could not be economically applied by commercial spraying techniques due to composition instability, difficulties in controlling viscosity and poor adhesion. Thus, there have been a need and a readily available market for a versatile silicate foam composition having a combination of high strength, good water resistance, good adhesion characteristics, and acceptable fabrication characteristics.